Can “as” ever properly mean “because”?

We often encounter as used to mean because. As we know, as is not merely ambiguous: it’s hexiguous or octiguous.

I’m especially uncomfortable when I find the usage in a technical paper¹, where precision (as I claim) trumps written or spoken style. I argue that as cannot stand in for because in a paper as rigorous as a specification.

But as I think about it, maybe I’m acting as a mere pedant; maybe I should lighten up a little. Do you folks think as I do? Or should I take it easy, just accept and go with it as the leaf accepts the breeze?

1. As in the current spec for the C programming language spec, for example.

I believe using as as a mere synonym of because is quite common, especially in prose that is intentionally formulaic rather than aimed at maximum clarity, which definitely includes many technical papers.

However, several style guides deplore this usage. Fowler's Modern English Usage recommends that as should only be so used to introduce a fact well known to the reader, as a mere reminder—not to introduce an ordinary reason or argument.

Caesar's dying words to Brutus were, "you too, my son". For the record, he didn't use those exact words, as he didn't speak English.

Using as to mean because is grammatical and common. From NOAD:

as 3 because; since : I must stop now as I have to go out.

That said, as you noted it does introduce a level of ambiguity that may be out of place in a strict piece of technical writing. While it would still not be wrong, it may not communicate as clearly as some readers would like.

If you are the writer, judge for yourself whether the usage is clear. If you are the reader and encounter the ambiguity, consider looking up the material in a different source.

edit

Sometimes writers do want the ambiguity, especially poets. Consider the opening to Fern Hill" by Dylan Thomas:

Now as I was young and easy under the apple boughs
About the lilting house and happy as the grass was green,
       The night above the dingle starry,
               Time let me hail and climb
       Golden in the heydays of his eyes

Now, as here may be read as "because" or "at the time that" or possibly other meanings. The ambiguity is one of the things that makes poetry convey so much meaning out of so few words.

I don't think we can have a problem with the use of as meaning “because” except when it causes the aforementioned ambiguities.

I teach Peruvian students in a bilingual school. They use as to mean “because” all the time because in Spanish, at least in Peru, como is used a lot more than porque. The problem, I think, only arises when, as happens frequently when I read their work, I take as to mean “because” and only realise at the end of the sentence that they meant “because”.

Taking exception to as for any other reason than this would, in my view, be pedantry.